ANTIMICROBIAL RESISTANCE OF ESCHERICHIA COLI CLINICAL ISOLATES CAUSING NEONATAL SEPSIS.
10 slide(s) – English – 2011-06-07
ANTIMICROBIAL RESISTANCE OF Escherichia coli CLINICAL ISOLATES CAUSING NEONATAL SEPSIS.
S. M. Soto, E. Guiral, J. Bosch and J. Vila
Department of Clinical Microbiology, Hospital Clinic, CRESIB, IDIBAPS, Barcelona, Spain.
Background and aims: Neonatal meningitis and septicemia caused by Escherichia coli and Streptococcus agalactiae are still major health problems in industrialized countries. The objective of the present work was to evaluate the antimicrobial resistance of E. coli strains causing early and late neonatal sepsis and to compare them with E. coli strains isolated from healthy neonates.
Methods: Twenty-seven E. coli strains from early neonatal sepsis, 40 from late neonatal sepsis and 28 from healthy neonates were studied. Minimal inhibitory concentrations were determined using the NM37 Panel (Siemens). Detection and characterization of determinants of resistance, integrons, and gyrA and parC mutations were carried out by PCR and sequencing.
Results: No differences were found in the resistance to the antimicrobial agents used to treat late neonatal sepsis (amikacin, ceftazidime and imipenem). However, resistance to chloramphenicol and piperacillin was significantly more frequent among strains collected from septic than from healthy neonates (p=0.05 and 0.0004, respectively). Two strains from neonatal sepsis presented BLEAS (CTX-M14 and CTX-M15, respectively). Twenty strains (30%) presented class-1 integrons with different combination of gene cassettes. Finally, four strains presented mutations in the amino acid codons Ser83Leu and Asp87Asn from the gyrA gene, two only Ser83Leu and one Asp87Lys. Of these, five also presented the Ser80Ile mutation and one the Gly84Val mutation in the parC gene.
Conclusions: E. coli strains causing neonatal sepsis were more resistant to the antimicrobial agents studied than the strains collected from healthy neonates except in those related to ciprofloxacin and gentamycin resistance.